It is well known in motor vehicles to provide an air bag module for protecting a vehicle occupant. It is also known to provide an air bag module including an inflatable restraint cushion and an inflator for generating gas to inflate the cushion upon sensing predetermined vehicle conditions. It is also known to provide air bag modules for side impact protection of the vehicle occupant.
The prior art side air bag modules typically include restraint cushions which protect the torso portion of the occupant and a separate cushion that protects the head portion of the occupant. Thus, a vehicle typically includes multiple restraint cushions to protect both the head and torso portions of the occupant which adds complexity to the side structure assembly. In addition, the typical head restraint cushion includes elaborate and complex attachment systems to the door, roof pillar, side pillars or other vehicle side structures by means of tethers, hook and loop fasteners, pivot pins, or other mechanical fastening devices to hold the cushion in a relatively stable lateral position to minimize lateral displacement of the cushion out through a window opening in the door during deployment.
The prior art has also suggested an air bag module having a single cushion which protects both the torso and head of the occupant, but which does not rely upon interaction with vehicle side structure for lateral restraint of the cushion. Instead, the cushion includes an external tether, adjacent the occupant, which is engaged by the occupant such that the cushion is pulled towards the vehicle occupant by the tether. The torso of the occupant initially engages the tether and pulls the upper portion of the cushion towards the head of the occupant such that the head is caught by the cushion. Such a cushion includes an upper portion and a lower portion and a tether being external to the cushion. The tether includes an upper end connected to the upper portion of the cushion and a lower end connected to the lower portion of the cushion. The tether is also located adjacent a vehicle occupant when the cushion is deployed such that the occupant engages the tether and the ends of the tether pull the cushion towards the occupant. Accordingly, this arrangement is designed to provide lateral support for the cushion while reducing reliance on interaction of the cushion with the vehicle side structure.